2017 Mustang GT Rear Clunk/Popping noise.....

Hello,

I just recently purchased a 2017 Mustang GT Performance Pack and I have an issue which I don't know if it's normal or not.

I have noticed at slow speeds(5-20mph) I sometimes get a popping/clunk noise that comes from the rear. It mostly does it as I am making 90 degree turns.

I recently lowered the car with Eibach Pro kit springs and I can't tell if I had the noise before I installed the springs. Car was lowered 2 days after I bought it brand new.

I already double checked the springs and everything is in place.

Any ideas???

same noise here. right after lowering on eibach sport lines. only when turning on going over uneven surfaces.

Anyone else getting this issue?

Same after Steeda Linears and Diff bushings. Happens at low speeds but mostly when shifting, not turning.

The Torsen diff in PP cars can be a little grabby and noisy in slow, tight turns.

ManBearPig said:

The Torsen diff in PP cars can be a little grabby and noisy in slow, tight turns.

Click to expand...

This, and the driveline is also just intrinsically clunky. People have had good luck minimizing it with swapping transmission fluid to BG Syncroshift II, installing the Steeda clutch spring, and even shimming different driveline components to get better angles between them.

I have the same problem when entering a parking lot with bumps. But when I'm driving in the Street them clunk noise stop.

Muff Muff said:

This, and the driveline is also just intrinsically clunky. People have had good luck minimizing it with swapping transmission fluid to BG Syncroshift II, installing the Steeda clutch spring, and even shimming different driveline components to get better angles between them.

Click to expand...

the problem was not there before though. Only after i lowered same as OP it happens.

s550_GT said:

the problem was not there before though. Only after i lowered same as OP it happens.

Click to expand...

Are you an Auto or Manual?

Muff Muff said:

Are you an Auto or Manual?

Click to expand...

manual

Could very well be your control arm bushings. Needs to be re clocked while sitting on it's wheels. Maybe a drive on lift.

I had a low speed clunk. Was a rear axle nut that was not properly torqued. I tightened it and threw on some red loctite and the noise went away. I think the spec is 135 ft lbs but I just tightened it as hard as I could with a breaker bar, because when I did 135 ft lbs the noise came back after a couple days.

S550GTCS said:

I had a low speed clunk. Was a rear axle nut that was not properly torqued. I tightened it and threw on some red loctite and the noise went away. I think the spec is 135 ft lbs but I just tightened it as hard as I could with a breaker bar, because when I did 135 ft lbs the noise came back after a couple days.

Click to expand...

Sounds familiar. There's a thread on here somewhere regarding the axle nuts which many have had issues with. Loads of guys checking their nuts and finding them loose Solution seems to be either re-tighten to the recommended spec using red locktite or...

...you'll have a failure as the nut rattles the ABS sensor causing damage. Car will go into limp mode with no TCS or ESC available. I ended up in this situation and had to replace the hub, axle nut and ABS sensor. Although parts are cheap ($150 total) and it was easy to do the work myself.

S550GTCS said:

I had a low speed clunk. Was a rear axle nut that was not properly torqued. I tightened it and threw on some red loctite and the noise went away. I think the spec is 135 ft lbs but I just tightened it as hard as I could with a breaker bar, because when I did 135 ft lbs the noise came back after a couple days.

Click to expand...

Can you tell me what socket size I need to tighten the axle nut?

Can't remember if it was a 32mm or 36mm.

Anybody know what the rear axle nut size is on the 15-17 Mustang GT?